Answer:
pretty sure it's d not sure also might be b but I think it's d
Answer: Yes and No
Explanation: If you mean to form a rock from scratch, then there's only pressure, heat and sedimentation involved. If you mean take shape from a piece of solid magma to a 'rock', then yes, it helps shape it and round it to be joined with the environment.
Answer:
The Carboniferous era had large deposits of coal matter in the soil. However there was absence of decomposers which gave rise to increased accumulation of organic matter in the soil.
Decomposers make use of oxygen to breathe in the soil due to their existence as animals and not plants. They inhale oxygen and give out Carbon dioxide.
Absence of these decomposers mean increased level of oxygen due to its non usage and reduction in CO2 which is the end product of respiration for the decomposers.
The sahara made migrating rough because it was a desert but it was easier to pass through rather than south afria going through jungles
